Stocks Buying

How do buying stocks get you money?
I’m thinking about buying a stock from Starbucks but I don’t know if I’ll actually get real money from doing that. Please answer my question in a way a 13-year-old can understand.
When you buy a stock, you are buying a small part of the company. When the company stock rises in price it means that the company is doing very well and the price that you bought the stock for will be less than it is worth now and you can sell it at that price. But the stock price of Starbucks stays pretty stable. If you bought a stock from starbucks at $15 and it went up to $20 and sold it, you would make $5.
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